Week 30 – July 20-26

2014 MOSQUITO REPORT: WEEK 30

Report based on data collected from traps deployed the week of July 20-26, 2014. Report prepared by Chan Suom, Dave Lawson, and Nate Boonisar.

1. CURRENT MOSQUITO ACTIVITY/TREND

CDC Light Traps:
CDC light trap collections were mixed this week. The towns of Bellingham, Braintree, Dedham, Foxboro, Millis, Norfolk, Randolph, Weymouth, and Wrentham collected higher than average numbers of mosquitoes, whereas Avon, Canton, Medway, Milton, Needham, Sharon, Walpole, and Westwood reported the opposite. The remaining towns collected average numbers of host-seeking mosquitoes.

Gravid Traps:
Gravid trap activity remains lower than the historical average. We have changed our mosquito attractant brew and hope this will imporove our collection numbers to give us a better representation of ovipositing mosquito activity in the county.

 2. CURRENT PREDOMINANT SPECIES

CDC Light Traps:
The most abundant mosquito species this week are Coquillettidia perturbans of which over 4,600 were collected from across the county. This was followed by Aedes vexans (800+). Ochlerotatus sollicitans and Oc. taeniorhynchus are becoming more numerous in Holbrook and Quincy though there doesn’t appear to be a mass emergence of any kind.

Gravid Traps:
Culex pipiens/restuans are the main species in these traps and their overall population is lower than average for this time of the season.

3. COMPARISON TO PREVIOUS SEASON

The overall mosquito population for host-seeking mosquitoes in CDC light traps is mixed when compared with the historical average (2007-2013). Coquillettidia perturbanspopulations are higher than average for the most part, but their peak has passed and their numbers continue to decline (from 5,500+ to 4,600+ specimens). Aedes vexanspopulations have also dropped from last week’s figures (from 1,100+ to 800+ specimens).

Gravid trap collections have been lower than average thus far this season. A change in our mosquito attractant brew may remedy this and return collections that better reflect the historical data and current activity of ovipositing mosquitoes.

Please refer to our surveillance charts for detailed trap collection data.

4. WEATHER SUMMARY

Temperatures this week were below normal to start and finish the week, and above normal in the middle of the week. No precipitation fell anywhere in the district during the week.

Total weekly rainfall: 0.00 inches (-0.69 in.)
Total Monthly rainfall: 2.80 inches (+0.24 in.)
Total Yearly rainfall: 22.21 inches (-1.62 in.)

5. NUMBER OF REQUESTS FOR SERVICE

We received 531 calls for service this week. We have recorded a total of 6,056 service requests for the year.

6. MCP/COMMISSION RESPONSE

The District is currently responding to requests for spraying with our evening ULV application program. Catch basins continue to be treated in the District’s towns with a majority of the towns’ treatments having been completed at this point. A small number of larvicide requests from residents continue to be checked as needed. In response to a finding of WNV in a pool of mosquitos in Canton, the district urged the town to post notifications warning residents, and especially the elderly, to take precautions to avoid mosquito bites.

Contact

144 Production Rd, Suite C

Walpole, MA 02081

Office: (781) 762-3681
Fax: (781) 769-6436